From what I've heard that's the story. The devs didn't want anyone to touch the map, which it clearly states on the workshop. Instead, the devs of the map wanted to do the edits themselves which Nebulous couldn't wait a month or so because it wasn't going to be an immediate thing, meaning it would take a while.
Saying I'm biased all the way is pretty funny, especially when facts are laid out that the devs of residential 17 explicitly do not want anyone to edit, redistribute, decompile, or share the .bsp.
it must mean I'm biased to say both that the devs don't want anyone to touch the map and that nebulous needed a map so they chose d47 because they weren't allowed to edit residential 17 themselves. Regardless, I may have come off as a dick when I said it, but it's their map, their choice. All I'm saying is that it has multiple areas ripped from HL2's C17, I'm making a point, not trying to be biased and tell one side of the story.
e; They could've allowed Neb to make the small changes to the rebel area, been given credit, and had their map be featured on a server that gets more players than any other HL2RP map. It'd be a win win situation, but like I said, their map their choice. Thus, Nebulous respected that.